Well tool



Feb. 13, 1962 J. w. KENNEDAY 3,020,958

WELL TOOL Filed June 25, 1958 3 Sheets-Sheet l 1l, an wiulv LP 4M' TMATTR NEY.

WELL TOOL 3 Sheets-Sheet 2 Filed June 25, 1958 FIG. IO.

INVENTOR.

ATTORNEY.

FIG. 9.

FIG. 8.

J. W. KEN NEDAY Feb. 13, 1962 WELL TOOL 3 Sheets-Sheet 3 Filed June 25,1958 iin- ATTORNEX United States Patent 3,020,958 WELL TOOL John W.Kenneday, Houston, Tex., assigner, by mesne assignments, to JerseyProduction Research Company, Tulsa, Okla., a corporation of DelawareFiled June 23, 1958, Ser. No. 743,697 9 Claims. (Cl. 166-118) Thisinvention relates to tool-s for carrying out workover operations inawell, such as sand washing operations.

The device to be described herein has particular use with wells having atubing arranged therein. The tubing may have its lower end positionedabove the bottom ot the well. By so positioning the tubing, exten-sionmembers may be run by wireline or other conventional means down thetubing. The extension members extend below the lower extremity of thetubing. Hence, workover operations can be conducted below the lowerextremity of the tubing which may be permanently arranged.

In carrying out certain workover operations, such as sand washing, atubular extension is lowered down the tubing. The well is then reversecirculated, that is, fluid is owed down the tubing-casing annulus and upthe tubular extension and tubing. The undesired sand in the well landtubing is thus removed to the surface.

'Ihe present invention provides novel means for latching the tubularextension member 25 to the col-lar recess in the tubing above theextension after the extension member has been lowered to the bottom ofthe well. A sleeve member 27 is provided on the upper section of thetubular extension member. The sleeve member is movable axially on theextension member. The latching means, such as latch dogs, are pivotallyconnected to the upper part of the sleeve member. A cup packer 29 ismounted to the sleeve member. Hence, upon reverse circulation the sleevemember moves upwardly on the extension member. With this upward movementof the sleeve member, the latching means engage the collar recess tolock the extension member `against upward movement.

Means are provided in the sleeve to prevent the tubular extension memberfrom moving upwardly like -a piston due to the reverse circulation. Thismeans preferably takes the form of at least one leaf spring having atleast one locking shoulder. A circular shoulder is provided on theextension member in such a position that upon reverse circulation thelocking shoulder will be moved into contact with the circular shoulderon the tubular extension member, thus preventing further upward movementof the extension member.

To unlock the latching dogs, direct circulation is started; that is,circulation down the tubing and then up the tubingcasing annulus. Thedirect circulation moves the sleeve member downwardly with respect tothe tubular extension to unlatch the latch-ing dogs.

In case of malfunction, provision is made in my new device to positivelyretract the latching dogs. A latch retracting means is connected to theslidable fishing neck. The latch retracting means is connected to theextension member by a frangible member, such as a shear pin. In the caseof malfunction, the fishing neck is jarred upwardly. The shear pin isbroken and the latch retracting means moved upwardly to positivelyretract the latching dogs.

Often, the material to be removed becomes packed. Packed material, suchas sand, is not easily removed by reverse circulation. One embodimentdisclosed herein includes a means permitting the loosening of thematerial to be removed. Collar lock dogs are provided in thisembodiment. The collar lock dogs are in addition to the latching dogs. Avcollar lockr dog actuating member for each lock dog is connected to theslidable tishng neck. If the reverse circulation does not result in thedesired removal of sand or debris, the fishing neck can then be drivendownward while reverse circulating so that the collar lock dogs areexpanded into the collar recess. Reverse circulation can then be ceased,and direct circulation employed to jet down into the sand or debris toloosen the sand or debris. Reverse circulation can then be renewed toremove the sand or debris.

From the foregoing it is seen that this invention includes a no-velmeans for latching an extension member in a collar recess of the tubing,means for positively retracting the latches in case of malfunction ofthe device during normal operations, and in one embodiment, meanspermitting the jetting of liuids against the sand or debris to loosen`said sand or debris if it 'should be so firmly packed as to not permiteffective removal by reverse circulation.

The invention, as well as its many advantages, will be furtherunderstood by reference to the following detailed description anddrawings, in which:

FIG. l is an elevational view showing the extension member latched inposition in a collar recess in the tublng;

FIG. 2 is an elevational View showing the extension member lowered to a.point below the next collar reces to that shown in FIG. 1;

FIG. 3 is an elevational view showing the extension member latched inposition in the next lower collar recess of the tubing;

FIG. 4 is an elevational view, partly in section, showing in detail thenew device when the extension member is in the unlatched position;

FIG. 5 is an elevational view, partly in section, showing in detail thedevice of FIG. 4 latched ina tubing collar recess; FIG. 6 is a viewtaken along lines 6 6 of FIG.'4;

FIG. 7 is a view taken along lines 7 7 of FIG. 4;

FIG. 8 isa view taken along lines 8 8 of FIG. 4;

FIG. 9 is a view taken along lines 9 9 of FIG. 5;

FIG. 10 is an elevational sectional view showing the mandrel used in thedevice of FIGS. 4 and 5;

FIG. ll is a view taken along lines 11 11 of FIG. 10;

FIG. 12 is an elevational view showing a second embodiment of theinvention with the extension member in the unlatched position;

FIG. 13 is `an elevational view, partly in section, showing in detailthe latching means of the deviceof FIG-12;

FIG. 14 isan elevational view, partly in section, show,- ing theapparatus for operating the collar lock dogs of the embodiment of FIGS.l2 and 13, with a section tubing 21 is positioned above the bottom ofthe well.

It is desired to remover material from the borehole and tubing. Thismaterial, here represented as sand; is

shown by numeral 24.. To remove the sand.24, a tubular' extension member2e' is lowered by means of a running tool 33 down to the desiredposition within the tubing 21..

The extension member 25 includes a'telescopic section 26. Disposed aboutthe extension member 25 is an elongated sleeve member 27, containing atits upper end a pair of latching dogs 28. A cup packer 29 is integrallymounted to the sleeve member 27. The tubular exten- The tubing stringmay be made upl sion member also has mounted adjacent its upper end amand-rel 30, having ports 39 formed therein. A iishing neck 31 isprovided at the upper end of the extension member.

FIGS. 1 to 3, inclusive, show the steps followed in removing the sand24. FIG. 1 shows the extension member 25 locked in position within thecollar recess formed by collar 22. The telescopic section 26 is in theextended position against the sand 24. Sand is then removed by reversecirculation until the extension member 26 has beenA fully extended. Inorder to remove more sand from the borehole, the running tool 33connected to the end of a wire line 32 is lowered to a position belowthe collar recess formed by threaded collar 23 after the latching dogshave been unlatched. This position is shown in FIG. 2. The telescopicsection 26 is then in its fully retracted position within extensionmember 25. Reverse circulation is then started, and the running tool 26is moved upwardly and the latching dogs 2S latched into the recessformed by collar 23. This position is shown in FIG. 3. The sand is thenfurther removed by reverse circulation. That is, uid is owed down thetubingcasing annulus, up the telescopic section 26 and extension member25, through ports 39, and on up to the surface through tubing 21.

Referring to FIGS. 4 through 11, the detailed structure of the elongatedsleeve member, mandrel, and fishing neck is shown. FIG. 4 shows therelative positions of the parts with the extension member in theunlatched position within the tubing 21, and FIG. 5 shows the positionsof the parts with the latching dogs 28 in the latched position withinthe collar recess, such as collar recess 23. A plurality of leaf springs49 Vare mounted within the elongated sleeve member 27. These leafsprings are flexible and normally biased outwardly. However, with theapplication of pressure from the bottom of the well, the leaf springsare curved inwardly, as shown in FIG. 5. Each of the leaf springs 49 hasat least one locking shoulder 41 extending perpendicularly from the axisof the leaf spring. A plurality of locking shoulders are shown in thefigures. The leaf springs are imbedded in the sleeve member 27 below theintegrally attached cup packer 29.

Latching dogs 28 are -attached to the upper portion of the sleeve member27 by means of pivot pins 42 disposed within recesses formed in thesleeve member 27. The latching dogs are guided outwardly upon upwardmovement of the sleeve member 27.

A plurality of ports 43 are formed within the sleeve member 27 at apoint above the cup packer 29. The ports 43 place the inside portion ofthe leaf springs 4t? in Huid communication with the fluid pressurewithin the tubing 21 and above the packer 29 through space 44. To latchthe latching dogs 28 in the collar recess, reverse circulation isapplied as the extension member is pulled upwardly by the running tool.The pressure below the cup packer 29 moves the axially slidable sleevemember 27 upwardly along the extension member, and the leaf springs 40inwardly against the outside portion of the extension member 25.Latching dogs 28 are guided in their outward movement against the collarrecess by the tapered portion of concave cone segments 46. The sleevemember is kept from rotating about the tubular extension member by meansof a guide pin 47 connected to the tubular extension member 2S andextending into a slot 48 formed in the inside periphery of the sleevemember 27.

The extension member 25 is prevented from moving upwardly like a pistonin response to the reverse circulation, by the provision of a recessformed therein to provide a circular shoulder 49. When the springs 4t)are biased inwardly by reverse circulation, one of the locking shoulders41 will be engaged by the tubular extension member shoulder 49, thuspreventing upward movement of the extension member.

The latching dogs 28.may be unlatched by the application of directpressure down the tubing 21. The fluid pressure communicates throughports 43 and space 44 to the springs 40. The springs are thus returnedto the position shown in FIG. 4, and the sleeve member 27 moved axiallydownward with respect to the tubing extension member to unlatch the dogs28.

The mandrel 30 s integrally connected to the upper portion of thetubular extension member 25 which forms a part of the mandrel.Diametrically oppositely placed elongated cut-outs are provided in themandrel 310. rI`he mandrel also includes an upper ring portion 51provided with diametrically opposite elongated cut-outs 52 (see FIG. 7).The cut-outs 50 and 52 extend along substantially the same longitudinalplane as the latching dogs 28.

A pair of cone supports 53 are threadedly connected to the fishing neck31 and extend through the cut-outs 52 in the ring portion 51. The conesupports 53 support the segmented concave cones 46. The tapered portionof each concave cone is slotted to receive a rocker arm 54 which ispivotally mounted within the slotted portion. The other extremity of therocker arm 54 is adapted to slidably move within slots 5S provided inthe latching dogs 28.

Frangible means, such as a shear pin 56, interconnects each cone support53 to the ring portion 51 of the mandrel 3i). During normal operations,the latching dogs 28 are unlatched by application of direct pressuredown the permanently arranged tubing 21 in the manner formerlydescribed, However, in the case of malfunction, a positive retractingmeans is provided to positively retract the latching dogs 28. This isdone by jarring the fishing neck upwardly to break the shear pin 56.Further upward pulling moves the slidable fishing neck with its attachedcone supports and concave cone segments upwardly. The rocker arm 54interconnecting the tapered portion of cone lsegments 46 with thelatching dogs 28 then positively retracts the latching dogs from thecollar recess as the cone segments move upwardly with the fishing neck.

In operating the embodiment shown in FIGS. 1 through l1, the extensionmember 25 is lowered by means of a running tool 33 connected to wireline 32 to the bottom of the borehole. Reverse circulation is then begunand,

if necessary, the extension member 25 pulled upwardly to move thelatching dogs 28 into the next upward collar recess. The reversecirculation moves the sleeve member 27 upwardly to securely latch thelatching dogs in the collar recess. The pressure also bends the springmembers 4t), as shown in FIG. 5, so that the locking shoulders 41 are inengagement with the shoulder 49 provided in the extension member 25.This prevents unwanted upward movement of the extension member. Afterthe telescopic section 26 has been fully extended, direct circulation isapplied down the permanently arranged tubing 21, through the port 43,sleeve member 27, and against the inside of the leaf springs. The leafsprings are thus returned to their original positions, the sleeve member27 moved downwardly with respect to the extension member, and the dogs28 unlatched- The extension member is then moved downwardly to theposition shown in FIG. 2, and reverse circulation again applied to latchthe latching dogs in the next lower collar recess, as shown in FIG. 3.If, for some reason, the latching dogs are not unlatched or not fullyunlatched, the pulling tool is jarred upwardly to break the shear pin56. Further upward movement of the fishing neck 31 positively unlatchesthe latching dogs 28.

A second embodiment of my invention is shown in FIGS. 12 through 16. Anelongated sleeve member 60 is mounted for slidable movement along theextension member 61. Attached to the sleeve member is a downwardlyfacing cup packer 62. Pivotally connected to the recesses formed in thetop of the sleeve member 60 by means of pivots d3 are latching dogs 64.Ports 65 are provided in the sleeve member 60 and disposed above thedownwardly facing cup packer 62.

The internal structure of the sleeve member 60 and its associated partsis not shown in FIGS. 12 through 16. However, the internal structure isexactly the same as the internal structure of the sleeve member 27 andits associated parts, described in relation to FIGS. 1 through 1l.

The extension member is lowered down the tubing 21. The extension memberis then raised while reverse circulation is applied. The reversecirculation moves sleeve member 60 upwardly to latch latching dogs 64 inthe collar recess. The locking shoulders on the leaf springs containedin sleeve member 60 engage a circular shoulder made in the extensionmember 61.

When it is desired to unlatch latching dogs 64, direct circulation isapplied through ports 65 and against the inside of the leaf springscontained within sleeve member 60. The sleeve member 60 is then moveddownwardly and the latching dogs unlatched.

A mandrel '66 is connected to the upper part of the extension member 61,with the upper portion of the extension member forming a part of themandrel. The mandrel includes a downwardly extending cylindrical member67 which is integrally connected to the upper portion of extensionmember 61.

Two diametrically spaced elongated cut-outs 68 are provided within themandrel 66. The cut-outs 68 are along substantially the samelongitudinal plane as the latching dogs 64. A pair of concave conesegments 69 are mounted for possible movement along the cut-out portions68. The cone segments 69 are supported by a circular cone support 70,having at its upper extremity a pair of lugs 71 which extend over andrest upon the upper extremity of extension member 61. Cone supportmember 70 is shear-pinned to the mandrel 66 by a shear pin 72. l

The tapered portions of the concave cone segments 69 are provided withslots 73. Rocker arms 74 are pivoted within the slots '73 by pivot pins75. The other end of rocker arm 74 slides within a slotted portion 76 oflatching dogs 64.

A pair of diametrically spaced openings 77 are provided in thedownwardly extending cylindrical portions 67 of the mandrel 66. Theseopenings are preferably separated from the elongated cut-outs 68 by a 90arc. Mounted for movement within the openings 77 are a pair of lockingdogs 7 S. Each locking dog 78 is normally biased in wardly by a coilspring 79 disposed within recesses formed in the cylindrical member 67and locking dogs 78. Locking dogs 78 taper upwardly with the taperedkportion being fitted with a groove S adapted to receive a track 80 onthe tapered portion of each collar locking, dog actuating, concave conesegments 81. The cone segments 81 are integrally connected to a slidablefishing neck 82 provided with fluid ports 83. The cone segments 81 areprovided with outwardly extending shoulders 100 in engagement withthecircular cone support 70.

As formerly stated, it often occurs that the desired removal of sand isnot accomplished byreverse circulation because of the packed conditionof the sand or debris within the borehole. When this situation arises,the slidable fishing neck 82 is jarred downwardly by jarring tool 33.This downward jarring moves the cone segment 81 vdownwardly and expandsthe locking dogs 78 into the recess of collar 23 against the bias ofcoil springs 79. Fluid is lthen jetted through ports 83 and extensionmember 61 directly against vthe sand or debris. To direct the pressureof the direct circulation through the tubular extension 61, rather thanin the extension member permanent tubing annulus, an upwardly facing cuppacker 84 is provided, During direct circulation or jetting, the sleevemember 60 is moved downwardly to unlatch latchling dogs 64; however, thelocking dogs 78 keep the extension member 61 locked in the recess ofcollar 23.

6 After the sand or debris has been loosened, reverse crculation can beresumed by pulling :upwardly on the slidable fishing neck 82 duringreverse circulation to retract the locking dogs 78 and again latch thelatching dogs 64.l The sand or debris is removed up the extension member61 through ports 83 and on -up to the surface.

in utilizing the embodiments shown in FIGS. l2 through 16, the stepsperformed are similar to the steps performed using the embodiments shownin FIGS. 1 through 11. The tool is first lowered to a point below thedesired collar recess. Reverse circulation is then begun as the tool ismoved upwardly, to move the sleeve member 6i) upwardly and thus latchthe latching dogs 64 to the desired collar recess. After the telescopicsection connected to the extension member has been fully extended,direct circulation is begun to move the sleeve 60 downwardly and unlatchthe latching dogs 64.

If, for some reason, the latches should not become fully unlatched, therunning tool is jarred upwardly. When upward jarring occurs, theshoulders of the cone segments 81 exert force against the upper portionof the cone supports 70 to break the shear pins 72. The concave conesegments 69 are then slidably moved upwardly within the cut-out portions68 and the latching dogs 64 positively retracted.

The device is removed to the surface after the workover operations havebeen completed by pulling up on the slidable fishing neck 82. The upwardpulling causes the cone support member 71 to engage the ring portion ofthe mandrel 66. Since the mandrel 66 is integrally connected to theextension member 61, the extension member is moved to the surface.

It is to be understood that various modifications and changes may bemade to the disclosed embodiments herein without departing from thescope of the appended claims. For example, the devices may be employedin tubing not permanently arranged in a well, such as a drill pipe.

I claim: p

1. For use in tubing arranged in a well, said tubing having a pluralityof vertically spaced internal recesses formed therein: a tubularextension member having a circular shoulder formed on its outerperiphery; an elongated sleeve member mounted about the tubularextension' member and slidable axially with respect to the tubularextension member and including, as a portion thereof, at least one leafspring having at least one locking shoulder to prevent upward movementof the tubular extension member by engaging said circular shoulderduring reverse circulation; a downwardly facing cup packer integrallybound to said sleeve member above the leaf springs, said packer beingadapted to force the leaf spring locking shoulders against the tubularextension member shoulder during reverse circulation; at least onelatching dog pivotally connected to the upper portion of the sleevemember; and guide means mounted on the tubular extension member forforcing the latch dog outwardly against the inside of the tubing uponupward movement of the sleeve -member when reverse circulation isinitiated whereby when the tubular extension member is lowered to thebottom of the well and the latch dog disposed adjacent lto a saidrecess, initiation of said reverse circulation will move the sleevemember upwardly and force 4the latehingdog into said recess and the leafspring locking lshoulder against the tubular extension member shoulder.

2. For use in tubing arranged in a well, said tubing having a pluralityof vertically spaced collar internal re-y cesses formed therein: atubular extension member having a circular shoulder formed on its outerperiphery; an elongated sleeve member mounted about the tubularextension member and slidable axially with respect to the tubularextension member and including, as a portion thereof, leaf springs eachhaving at least one locking shoulder to prevent upward movement of thetubular exf tension member by engaging said circular shoulder duringreverse circulation; `a downwardly facing cup packer integrally bound tosaid sleeve member above the leaf springs and below at least one pointformed in .the sleeve member whereby fluid owed through the port duringdirect circulation equalizes the pressure across the leaf springs anddisengages the leaf spring locking shoulders from the tubular extensionmember circular shoulder; collar recess latches connected to the upperportion of the sleeve member; a slidable fishing neck; latch retractingmeans connected to the fishing neck and to the latches; and frangiblemeans connecting the latch retracting means to the extension memberwhereby when the tubular extension member is lowered to the bottom ofthe borehole and the latches disposed adjacent to a said collar recess,reverse circulation will move the sleeve member upwardly and force thelatches into said collar recess and the leaf spring locking shouldersagainst the tubular extension member, and after completion of a washcycle, terminating the reverse circulation and initiating a directcirculation will unlatch the latches and disengage the leaf springlocking shoulders from the tubular extension member, and in case ofmalfunction of the latches, the jerking of the fishing neck upwardlywill break the frangible means and retract the latches.

3. For use in tubing arranged in a well, said tubing having a pluralityof vertically spaced collar internal recesses formed therein: a tubularextension member having a circular shoulder formed on its outerperiphery; an elongated sleeve member mounted about the tubularextension member and slidable axially with respect to the tubularextension member and including, as a portion thereof, leaf springs eachhaving at least one locking shoulder to prevent upward movement of thetubular extension member by engaging said circular shoulder duringreverse circulation; a pair of diametrically spaced latching dogspivotally connected to the upper portion of the sleeve member; adownwardly facing cup packer integrally bound to said sleeve memberabove the leaf springs and below at least one port formed in the sleevemember whereby fluid owed through the port during direct circulationequalizes the pressure across the leaf springs to release the latchingdogs and disengage the leaf spring locking shoulders from the tubularextension member circular shoulder; a mandrel connected to the upperportion of the tubular extension member; a slidable shing neck; taperedlatch retracting means connected to the fishing neck and serving toguide a latching dog during movement of said latching dog into a saidrecess; latch actuating means interconnecting the latch retracting meansand latching dogs; and a frangible means connecting the tapered latchretracting means to the mandrel, whereby when the tubular extensionmember is lowered into the bottom of the borehole and the latching dogsdisposed adjacent to said collar recess, reverse circulation will movethe sleeve member upwardly and force the latching dogs into said collarrecess by cam action against the tapered means and the leaf springlocking shoulders -against the tubular extension member, and aftercompletion of a wash cycle, terminating the reverse circulation andinitiating a direct circulation will unlatch the latching dogs anddisengage the leaf spring locking shoulders from the tubular extensionmember, and in case of malfunction of the latches, the jerking of theshing neck upwardly will break the frangible means and retract thelatching dogs.

4. For use in a tubing arranged in a well, said tubing having aplurality of vertically spaced collar internal recesses formed therein:a tubular extension member having a circular shoulder formed on itsouter periphery; an elongated sleeve member mounted about the tubularextension member and slidable axially with respect to the tubularextension member and including, as a portion thereof, leaf springs eachhaving at least one locking shoulder to prevent upward movement of thetubular extension member by engaging said circular shoulder duringreverse circulation; a pair of diametrically spaced latching dogspivotally connected to the upper portion of the sleeve member to latchinto a said recess upon upward movement of :the sleeve member duringreverse circulation; a downwardly facing cup packer integrally bound tosaid sleeve member above the leaf springs and below at least one portformed in the sleeve member whereby uid owed through the port duringdirect circulation equalizes the pressure across the leaf springs torelease the latching dogs and disengage the leaf spring lockingshoulders from the tubular extension member circular shoulder; a mandrelconnected to the upper portion of the tubular extension member andhaving at least one port in communication with the tubing-mandrelannulus; a fishing neck; a pair of cone supports connected to thefishing neck; a concave cone segment connected to each cone support andadapted for guided slidable movement within the mandrel, the taperedportion of each concave cone segment serving to guide said latching dogduring movement thereof into said recess; latch actuating meansinterconnecting the concave cone segments and latching dogs; and a shearpin interconnecting each cone support to the mandrel whereby when thetubular extension member is lowered into the borehole, reversecirculation will move the sleeve member upwardly and latch the latchingdogs into saidV recess by cam action against the tapered means and theleaf spring locking shoulders against the tubular extension member, andafter a completion of a wash cycle, terminating the reverse circulationand initiating a direct circulation will unlatch the latching dogs anddisengage the leaf spring locking shoulders, and in case of malfunctionof the latching dogs, the jerking of- -the fishing neck upwardly willshear the shear pins land retract the latching dogs.

5f. For use in tubing arranged in a well, said tubing having a pluralityof vertically spaced collar internal recesses formed therein: a tubularextension member having a circular shoulder formed on its outerperiphery; an elongated sleeve member mounted about the tubularextension member and slidable axially with respect to the tubularextension member and including, as a portion thereof, leaf springs eachhaving at least one locking shoulder to prevent upward movement of thetubular extension member by engaging said circular shoulder duringreverse circulation; a pair of diametrically spaced latching dogspivotally connected to the upper portion of the sleeve member to latchinto a said recess during reverse circulation; a downwardly facing cuppacker integrally bound to said sleeve member above the leaf springs andbelow at least one port formed in the sleeve member whereby uid flowedthrough the port during direct circulation equalizes the pressure acrossthe leaf springs to release the latching dogs and disengage the leafspring locking shoulders from the tubular extension member circularshoulder; a mandrel integrally connected to the upper portion of thetubular extension member, said mandrel having diametrically oppositeelongated cut-outs and an upper ring portion having inside diametercut-outs extending along substantially the same longitudinal and axialplane as the latching dogs, and at least one port in communication withthe tubing-mandrel annulus; a fishing neck; a pair of cone supportsconnected to the fishing neck and extending through the inside diametercut-outs of the upper ring portion of the mandrel; a concave conesegment connected to each cone support and adapted for slidable movementwithin the elongated cut-outs in the mandrel, the tapered portion ofeach concave cone segment serving to guide a latching dog duringmovement of the latching dog into said recess; latch actuating meansinterconnecting the concave cone segments and latching dogs; and a shearpin interconnecting each cone support to the ring portion of the mandrelwhereby when the tubular extension member is lowered into the borehole,reverse circul-ation will move the sleeve member upwardly and latch thelatching dogs into said recess by cam action against the tapered meansand the leaf spring locking shoulders against the tubular extensionmember, and, after completion of a wash cycle, terminating the reversecirculation and initiating a direct circulation will unla-tch thelatching dogs and the leaf spring locking shoulders, and in case ofmalfunction of the latching dogs, the jerking of the shing neck upwardlywill shear the shear pins and retract the latching dogs.

6. For use in tubing arranged in a well, said tubing having a pluralityof vertically spaced collar internal recesses formed therein: a tubularextension member having a circular shoulder formed on its outerperiphery; an elon- -gated sleeve member mounted about the tubularextension member and slidable axially with respect to the tubularextension member and including, as a portion thereof, leaf springs eachhaving lat least one locking shoulder to prevent upward movement of thetubular extension member by engaging said circular shoulder duringreverse circulation; a pair of diametrically spaced slotted latchingdogs pivotally connected to the upper portion of the sleeve member tolatch into a said recess during reverse circulation; a downwardly facingcup packer integrally bound to said sleeve member above the leaf springsand below at least one port formed in the sleeve member whereby `fluidflowed through the port on direct circulation equalizes the pressureacross the leaf springs to release the latching dogs and disengage theleaf spring locking shoulders from the tubular extension member circularshoulder; a mandrel integrally connected `to the upper portion of thetubular extension member, said mandrel having diametrically oppositeelongated cut-outs and an upper ring portion having inside diametercut-outs extending along substantially the same longitudinal and axialplane as the latching dogs, and at least one port in communica- .tionwith the tubing-mandrel annulus; a fishing neck; a pair of cone supportsconnected to the fishing neck and extending through the inside diametercut-outs of the upper ring portion of the mandrel; a concave conesegment connected to each cone support and adapted for slidable movementwithin the elongated cut-outs in the mandrel, the tapered portion ofeach concave cone segment being slotted and serving to guide a latchingdog during movement of the latching dog into said recess; a rocker armpivotally mounted in each of said cone segment slots and connected to alatching dog; and a shear pin interconnecting each cone support to thering portion of the mandrel whereby when the tubular extension member islowered into the borehole, reverse circulation will move the sleevemember upwardly and latch the latching dogs into Isaid recess by camaction against the tapered means and the leaf spring locking shouldersagainst the tubular extension member, and, after completion of a washcycle, terminating the reverse circulation and initiating a directcirculation will unlatch the latching dogs and the leaf spring lockingshoulders, and in case of malfunction of the latching dogs, the jerkingof the fishing neck upwardly will shear the shear pins land retract thelatching dogs.

7. For use in a tubing arranged in -a well, said tubing having aplurality of vertically spaced internal recesses formed therein: atubular extension member; an elongated sleeve member mounted about thetubular extension member and slidable axially with respect to thetubular extension member; a downwardly facing cup packer integrallybound to said sleeve member; latches connected to the upper portion ofthe sleeve member; guide means mounted on the tubular extension memberfor guiding said latches into engagement with a said recess upon reversecirculation; `locking dogs mounted in the tubular extension member; amovable shing neck having jarring of the fishing neck whereby when theshing neck is jarred downwardly, the locking dogs will expand into saidrecess.

8. For use in a tubing arranged in a well, said tubing having aplurality of vertically'spaced collars forming collar internal recesses;a tubular extension member having a circular shoulder formed on itsouter periphery; an elongated sleeve member mounted about the tubulareX- tension member and slidable axially with respect to the tubularextension member land including, as a portion thereof, leaf springs each`having at least one locking shoulder to prevent upward movement of thetubular extension member by engaging said circular shoulder duringreverse circulation; latches pivotally connected to the upper portion ofthe sleeve member; guide means for causing said latches lto engage asaid internal collar recess upon reverse circulation; a downwardlyfacing cup packer integrally bound to said sleeve member labove the leafsprings and below at least one port formed in the sleeve member wherebyfluid flowed through the port on direct circulation equalizes thepressure across the leaf springs to release the latches land disengagethe leaf spring locking shoulders from the tubular extension membercircular shoulder whereby when the tubular extension member is loweredinto the well, reverse circulation will latch the latches in said collarrecess and the leaf spring locking shoulders against the tubularextension shoulder, and after completion of a wash cycle, terminatingthe reverse circulation and initiating a direct vcirculation willunlatch the latches and the leaf spring locking shoulders; collarlocking dogs mounted in the tubular extension member; a movable fishingneck having actuating means to actuate the colla-r locking dogs intolocking engagement with the said internal coll-ar recess upon downwardjarring of the fishing neck whereby when the fishing neck is jarreddownwardly, the collar locking dogs will expand into said internalcollar recess.

9. For use in tubing arranged in a well, said tubing having a pluralityof vertically spaced collars forming collar internal recesses; a tubularextension member having a circular shoulder formed on its outerperiphery; an elongated sleeve member mounted about the tubular eX,-tension member and slidable axially with respect to the tubularextension member and including, 2.8 a portion thereof, leaf lsprings`each having at least one locking shoulder to prevent upward movement ofthe tubular extension member by engaging said circular .shoulder duringreverse circulation; a pair of diametrically spaced latching dogspivot-ally connected to the upper portion of the sleeve member yto latchyinto a said internal recess during reverse circulation; a downwardlyfacing cup packer integrally bound to said sleeve member above the leafsprings and below at Ileast one port formed in the sleevev memberwhereby fluid iiowed through the port on direct circulation equalizesthe pressure across the leaf springs to release the latching dogs anddisengage the leaf spring locking shoulders from the tubular extensionmember circular shoulder; a mandrel integrally connected to the upperportion of the tubular extension member, said mandrel having twodiametrical openings; collar locking dogs, One

for each opening in said (mandrel, adapted for movement within saidopenings; a latching dog cone support connected to the mandrel; a pairof concave cone segments integrally connected to the cone support; thetapered portion of each concave cone segment serving to guide a latchingdog during movement of the latching dog into.

said internal recess whereby when the tubular extension is lowered intothe well, reverse circulation will latch the latching dogs into saidcollar recess by cam action against the tapered means and the leafspring locking shoulders against the tubular extension member shoulder;a fishing neck slidably extending intoithe mandrel; and a pair of collarlocking dog actuating concave cone segments, one

1 1 for actuating each collar locking dog, integrally connecd to `theshing neck whereby, when the shng neck is jarred downwardly, the collarlocking dogs will expand into said collar internal recess.

References Cited in the file of this patent UNITED STATES PATENTS FoxSept. 6, 1932 Page Sept. 18, 1951 Page Sept. 25, 1956 Tausch July 23,1957 Fredd Oct. 14, 1958

